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Government policies and corporate strategies aimed at reducing methane emissions from the oil and gas sector increasingly rely on measurement-informed emissions inventories, as conventional bottom-up inventories poorly capture temporal variability and the heavy-tailed nature of methane emissions. This work is based on an 11-month methane measurement campaign at oil and gas production sites. We find that operator-level top-down methane measurements are lower during the end-of-project phase than during the baseline phase. However, gaps persist between end-of-project top-down measurements and bottom-up inventories, which we reconcile with high-frequency data from continuous monitoring systems (CMS). Specifically, we use CMS to (i) validate specific snapshot measurements and determine how they relate to the temporal emissions profile of a given site and (ii) create a measurement-informed, site-level inventory that can be validated with top-down measurements to update conventional bottom-up inventories. This work presents a real-world demonstration of how to reconcile CMS rate estimates and top-down snapshot measurements jointly with bottom-up inventories at the site-level. More broadly, it demonstrates the importance of multi-scale measurements when creating measurement-informed emissions inventories, which is a critical aspect of recent regulatory requirements in the Inflation Reduction Act, voluntary methane initiatives such as OGMP 2.0, and corporate strategies.

Characterizing methane emissions on oil and gas sites often relies on a forward model to describe the atmospheric transport of methane. Here we compare two forward models: the Gaussian plume, a commonly used steady-state dispersion model, and the Gaussian puff, a time varying dispersion model that approximates a continuous release as a sum over many small “puffs”. We compare model predictions to observations from a network of point-in-space continuous monitoring systems (CMS) collected during a series of controlled releases. Specifically, we use the Pearson correlation coefficient and mean absolute error (MAE) as metrics to assess the fit of the model predictions to the observed concentrations in terms of pattern and amplitude, respectively. The Gaussian puff outperforms the Gaussian plume using both metrics with average correlation coefficients of 0.38 and 0.31 and average MAEs of 0.70 and 0.74, respectively. We provide computationally efficient and scalable implementations of the Gaussian puff model. Compared to regulatory-grade, Gaussian puff-based models like CALPUFF, our implementations have higher spatial and temporal resolution and require only essential and practically available meteorological information. These features enable near real-time methane mitigation applications on oil and gas sites and might be useful for near-field atmospheric transport modeling applications more broadly.

Government policies and corporate strategies aimed at reducing methane emissions from the oil and gas sector increasingly rely on measurement-informed emissions inventories, as conventional bottom-up inventories poorly capture temporal variability and the heavy-tailed nature of methane emissions. This work is based on an 11-month methane measurement campaign at oil and gas production sites. We find that basin- and operator-level top-down measurements show lower methane emissions during end-of-project than during baseline 9-months earlier. However, gaps persist between end-of-project top-down measurements and bottom-up inventories, which we reconcile with high-frequency data from continuous monitoring systems (CMS). Specifically, we use CMS to (i) assess the validity of snapshot measurements and determine how they relate to the temporal emissions profile of a given site and (ii) create a near-real time, measurement-informed inventory that can be cross-checked with top-down measurements to update conventional bottom-up inventories. This work presents a real-world demonstration of how CMS can be used to reconcile top-down snapshot measurements with bottom-up inventories at the site-level. More broadly, it demonstrates the importance of multi-scale measurements when creating measurement-informed emissions inventories, which is a critical aspect of recent regulatory requirements in the Inflation Reduction Act, voluntary methane initiatives such as OGMP 2.0, and corporate strategies.

Human activity has fundamentally altered wildfire on Earth, creating serious consequences for human health, global biodiversity, and climate change. However, it remains difficult to predict fire interactions with land use, management, and climate change, representing a serious knowledge gap and vulnerability. We used expert assessment to combine opinions about past and future fire regimes from 98 wildfire researchers. We asked for quantitative and qualitative assessments of the frequency, type, and implications of fire regime change from the beginning of the Holocene through the year 2300. Respondents indicated that direct human activity was already influencing wildfires locally since at least ~12,000 years BP, though natural climate variability remained the dominant driver of fire regime until around 5000 years BP. Responses showed a ten-fold increase in the rate of wildfire regime change during the last 250 years compared with the rest of the Holocene, corresponding first with the intensification and extensification of land use and later with anthropogenic climate change. Looking to the future, fire regimes were predicted to intensify, with increases in fire frequency, severity, and/or size in all biomes except grassland ecosystems. Fire regime showed quite different climate sensitivities across biomes, but the likelihood of fire regime change increased with higher greenhouse gas emission scenarios for all biomes. Biodiversity, carbon storage, and other ecosystem services were predicted to decrease for most biomes under higher emission scenarios. We present recommendations for adaptation and mitigation under emerging fire regimes, concluding that management options are seriously constrained under higher emission scenarios.Competing Interest StatementThe authors have declared no competing interest. Introduction Methods and materials Results and discussion Timing and type of future fire regime change Consequences of fire regime change Our capacity to prevent, control, or adapt to future fire regimes Charting a course in a world of uncertainty Expert assessment application in fire management

Chronic exposure to cocaine alters inflammatory signalling pathways in the brain, activates microglia and induces cognitive and motivational behavioural impairments. The endocannabinoid system may mediate cocaine’s effects. In the present study, we investigated the modulatory effects of the cannabinoid CB2 receptor agonist JWH-133 on cocaine-induced inflammation and motivational behavioural changes in vivo, and the possible effects of fractalkine (CX3CL1) on primary microglia metabolic activity and its subsequent contribution to cocaine-induced neurotoxicity. Our findings show that the CB2-specific receptor agonist, JWH-133, significantly attenuated the reinstatement of cocaine-induced CPP, increased Δ-FOSB expression in the nucleus accumbens (Nac), increased CX3CL1 levels in the ventral tegmental area (VTA) and prefrontal cortex (PFC), and decreased IL-1β in the PFC and NAc of cocaine treated animals. On the other hand, stimulation of the cortical primary microglial cells with CX3CL1 induced a biphasic effect. At a low concentration of 50 nM, CX3CL1 decreased mitochondrial oxidative metabolism vs glycolysis, and decreased the release of the proinflammatory cytokine, IL-1β, but did not affect TNFα. However, a dose of 100 nM of CX3CL1 increased mitochondrial oxidative metabolism, and both, IL-1β and TNFα release. These findings demonstrate that CB2 cannabinoid receptor modulation alters cocaine-induced reward-seeking behaviour and related neurobiological changes and highlights a potential role for CX3CL1 in the modulation of microglial metabolic and inflammatory-mediated activities.

Characterizing methane emissions on oil and gas facilities often relies on a forward model to describe the atmospheric transport of methane. Here we compare two forward models: the Gaussian plume, a commonly used steady-state dispersion model, and the Gaussian puff, a time varying dispersion model that approximates a continuous release as a sum over many small "puffs". We compare model predictions to observations from a network of point-in-space continuous emissions monitoring systems (CEMS) collected during a series of controlled releases. Specifically, we use the Pearson correlation coefficient and mean absolute error (MAE) as metrics to assess the fit of the model predictions to the observed concentrations, with the former assessing the fit of pattern and the latter the fit of amplitude. The Gaussian puff outperforms the Gaussian plume using both metrics with average correlation coefficients of 0.38 and 0.31 and average MAEs of 0.70 and 0.74, respectively. We also investigate how the frequency at which puffs are generated affects the accuracy and computational cost of the Gaussian puff and propose guidelines for choosing an appropriate value. Finally, we provide open-source implementations of the Gaussian puff model in Python and R that are tailored for use on oil and gas facilities.

We propose a generic, modular framework for emission event detection, localization, and quantification on oil and gas facilities that uses concentration data collected by point-in-space continuous emissions monitoring systems (CEMS). The framework uses a gradient-based spike detection algorithm to estimate emission start and end times (event detection) and pattern matches simulated and observed concentrations to estimate emission source location (localization) and rate (quantification). We test the framework on a month of single-source controlled releases ranging from 0.50 to 8.25 hours in duration and 0.18 to 6.39 kg/hr in size conducted at the Methane Emissions Technology Evaluation Center in Fort Collins, Colorado. All controlled releases are identified and 82% are localized correctly. For emissions < 1 kg/hr, the framework underestimates by 37.2% on average, with 90% of rate estimates within a factor of [-4.6, 2.8] or a percent difference of [-78.1%, 178.6%]; for emissions > 1 kg/hr, the framework overestimates by 1.5% on average, with 90% of rate estimates within a factor of [-2.0, 1.8] or a percent difference of [-49.6%, 77.4%] from the true rates. Potential uses for the proposed framework include near real-time alerting for rapid emissions mitigation and emission quantification for data-driven inventory estimation on production-like facilities.

What are the affordances of reading apocalyptic fiction under apocalyptic conditions, when a realism without apocalypse hardly seems realistic at all? What does it mean that our attempts to imagine...

Methane mitigation from the oil and gas (O&G) sector represents a key near-term global climate action opportunity. Recent legislation in the United States requires updating of current methane reporting programs for oil and gas facilities with empirical data. While technological advances had led to improvements in methane emissions measurements and monitoring, the overall effectiveness of mitigation strategies rests on quantifying spatially and temporally varying methane emissions more accurately than current approaches. In this work, we demonstrate a quantification, monitoring, reporting, and verification framework that pairs snapshot measurements with continuous emissions monitoring systems (CEMS) to reconcile measurements with inventory estimates and account for intermittent emissions events. We find site-level emissions exhibit significant intra-day and daily emissions variation. Snapshot measurements of methane can span over three orders of magnitude and may have limited application in developing annualized inventory estimates at site-level. Consequently, while official inventories underestimate methane emissions on average, emissions at individual facilities can be higher or lower than inventory estimates. Using CEMS, we characterize distributions of frequency and duration of intermittent emission events. Technologies that allow high sampling frequency such as CEMS, paired with a mechanistic understanding of facility-level events, are key to accurate accounting of short-duration, episodic, and high-volume events that are often missed in snapshot surveys, and to scale snapshot measurements to annualized emissions estimates.

There have been many extreme fire seasons in Maritime Southeast Asia (MSEA) over the last two decades, a trend which will likely continue or accelerate due to climate change. Fires, in turn, are a major driver of atmospheric carbon monoxide (CO) variability, especially in the Southern Hemisphere. Here we attempt to maximize the amount of CO variability that can be explained via human-interpretable statistical models that use only climate mode indices as predictor variables. We expand upon previous work through the complexity at which we study the connections between climate mode indices and atmospheric CO (a proxy for fire intensity). Specifically, we present three modeling advancements. First, we analyze five different climate modes at a weekly timescale, which increases explained variability by 15% over models on a monthly timescale. Second, we accommodate multiple lead times for each climate mode index, finding that some indices have very different effects on CO at different lead times. Finally, we model the interactions between climate mode indices at weekly timescales, which provides a framework for studying these interactions at a higher level of complexity than previous work. Furthermore, we perform a stability analysis and show that our model for the MSEA region is robust, which adds weight to the scientific interpretation of the selected model terms. We believe that the complex relationships quantified here will be useful for scientists studying modes of variability in MSEA and for forecasters looking to maximize the information they glean from climate modes.

The TROPOspheric Monitoring Instrument (TROPOMI) is the satellite instrument on board the Copernicus Sentinel-5 Precursor satellite launched on 13 October 2017. Data products include column estimates of ozone, nitrogen dioxide, methane, carbon monoxide, among others, and feature unprecedent high spatial resolution. These new data products provide opportunities to gain detailed insights into emissions and their sources on scales previously not feasible. We present results from five student teams investigating TROPOMI observations in a semester-long statistical and machine learning analysis practicum under the joint guidance of an atmospheric scientist and statistician. The analysis follows agile practices, where initial results inform the next analysis step. The focus is on the United States, specifically the investigation of methane emissions from natural gas production in key geological basins.

Purpose The purpose of this paper is to explore how an innovation in the University Management Information System was leveraged to incorporate library data by an initially sceptical strategic management team. The rationale was to extract evidence of correlations between library use and student achievement. This kind of information is of particular interest to the institution, which is at present dealing with crises popularly summarised in the slogan “#FeesMustFall” among students who suffer from the effects of poverty and exclusion in higher education. Comment is offered on some of the relationships between student library behaviour before, during and after the nationwide disruptions that destabilised universities and threatened their survival at the end of 2016, just before the final examination period. Design/methodology/approach Data were extracted from the data warehouse from the comparative demographic perspectives of students’ degrees of disadvantage in an effort to uncover any hitherto hidden patterns of library use. Findings The use of the library as expressed by footfall and loans was mapped against students’ pass rates and their collective GPA, indicating that increased library use correlates positively with better academic performance. Some of the initial correlations between student library behaviour before, during and after the nationwide disruptions that destabilised universities and threatened their survival at the end of 2016 just before the final examination period are explored. The effects that library closures (under threat of damage) at a critical time in the academic year might have had on library use and on student performance are interrogated. Practical implications Students on financial aid, which was used as an indicator of disadvantage, come from schools and environments where access to information technology and libraries is very limited, so that library habits are either poorly established or not at all. At the University of Cape Town (UCT), considerable support is in place for students to encourage the development of library habits. An analysis of available data indicates that students who have acquired library habits regardless of unfavourable financial circumstances do not exhibit behaviour and academic outcomes markedly different from that of their more privileged peers. Originality/value Combining library data with data from the university data warehouse is a new approach in South Africa. It is an approach that is of value both to the library and the institution at large and has brought meaningful insights into the role the academic library might be seen to play in promoting student academic achievement.

Effective cleaning of chromatography resin is required to prevent fouling and maximize the number of processing cycles which can be achieved. Optimization of resin cleaning procedures, however, can lead to prohibitive material, labor, and time requirements, even when using milliliter scale chromatography columns. In this work, high throughput (HT) techniques were used to evaluate cleaning agents for a monoclonal antibody (mAb) polishing step utilizing Fractogel(®) EMD TMAE HiCap (M) anion exchange (AEX) resin. For this particular mAb feed stream, the AEX resin could not be fully restored with traditional NaCl and NaOH cleaning solutions, resulting in a loss of impurity capacity with resin cycling. Miniaturized microliter scale chromatography columns and an automated liquid handling system (LHS) were employed to evaluate various experimental cleaning conditions. Cleaning agents were monitored for their ability to maintain resin impurity capacity over multiple processing cycles by analyzing the flowthrough material for turbidity and high molecular weight (HMW) content. HT experiments indicated that a 167 mM acetic acid strip solution followed by a 0.5 M NaOH, 2 M NaCl sanitization provided approximately 90% cleaning improvement over solutions containing solely NaCl and/or NaOH. Results from the microliter scale HT experiments were confirmed in subsequent evaluations at the milliliter scale. These results identify cleaning agents which may restore resin performance for applications involving fouling species in ion exchange systems. In addition, this work demonstrates the use of miniaturized columns operated with an automated LHS for HT evaluation of chromatographic cleaning procedures, effectively decreasing material requirements while simultaneously increasing throughput. Biotechnol. Bioeng. 2016;113: 1251-1259. © 2015 Wiley Periodicals, Inc.

The composition and origin of foulants and their spatial distribution within the particles of the Protein A MabSelect resin cycled in a mAb purification process are determined using electron and confocal microscopy techniques with gold and fluorescently labeled protein probes that associate with the foulants. The results show that the foulants are primarily related to the mAb product, are heterogeneously dispersed both on the outer surface and in the interior of the resin beads, and accumulate only when loading the conditioned CHO cell culture supernatant. Insignificant accumulation is seen if the process is run with purified mAb or with the null cell culture supernatant. When bound to the Protein A ligand, the mAb responsible for the observed fouling behavior is shown to associate with BSA and α-lactalbumin. This property is exploited using labeled versions of these lipophilic proteins to assess the effectiveness of improved resin cleaning processes and to elucidate the fouling mechanism. Resin fouling for this mAb appears to be consistent with the occurrence of conformational changes that occur upon binding, which, in turn, facilitate association of lipophilic proteins with the mAb. Upon desorption at low pH, these destabilized mAb complexes are deposited on and within the resin growing with each cycle and eventually leading to significant degradation of process performance.

The structural and functional characteristics of the Protein A MabSelect resin are determined for a virgin sample and for samples removed from a column that had been operated in an antibody capture process which had shown losses in product recovery over fewer than 20 cycles. Compared to the virgin resin, the cycled samples show reduced porosity and apparent pore size based on inverse size exclusion chromatography while transmission electron microscopy (TEM) shows accumulation of foulants on the cycled resin. Adsorption isotherms, batch adsorption kinetics, and batch desorption kinetics, obtained using the antibody in purified form, show that the cycled samples have about 10% lower binding capacity and slower mass transfer. Confocal scanning laser microscopy shows, however, that different degrees of fouling exist for different beads in the cycled samples, which may correspond to the existence of areas exposed to minimal or no flow in the process column. Replacing the standard cleaning procedure with an improved multi-step cleaning protocol prevented the accumulation of foulants in the resin beads, as evident from TEM, and resulted in a stable operation with high recovery.

Between 1992 and 2003, services for homeless veterans at the Veterans Affairs Greater Los Angeles Healthcare System went from inappropriate utilization of hospital medical and psychiatric beds, to a continuum of residential treatment, transitional housing, and employment programs through arrangements with private agencies. The authors use elements of Hasenfeld and Brock's Political Economy Model (1991) to explain this transformation in service delivery that was spearheaded by a VA social work leadership team. It is argued that three driving forces crucial to program implementation were present: technological certainty, economic stability, and concentration of power. Evidence of the implementation's impact includes creation of new homeless program beds, a reduction in use of medical/psychiatric beds, and a large number of formerly homeless veterans with housing and employment at program discharge. Study limitations and implications for future studies are discussed.

This is a post-print/preprint of an article published by Emerald in Performance Measurement and Metrics, VOL 11, available: http://dx.doi.org/10.1108/14678041011064043., Purpose – The purpose of this paper is to explore the use made of the Research Commons during its first year of operation in an attempt to establish whether it actually provides a genuinely new and different service from the point of view of the end‐users, and whether a facility such as this could indeed be presumed to support research and enhance research output at the university. Design/methodology/approach – Using Lippincott's assessment grid, an attempt was made to assess activities in the Research Commons according to the dimensions of extensiveness, efficiency, effectiveness, service quality and usefulness. Methodology was mixed, with quantitative and qualitative components that logged the extent and nature of the use of the various facilities in the Research Commons and sought to establish from stakeholder perceptions whether the services on offer are regarded as substantially different from those in the undergraduate Knowledge Commons and whether they are indeed seen to be supporting research activities. Findings – It was found that a combination of numerical and qualitative measurements has yielded sufficient evidence for the drawing of preliminary conclusions. The evidence gathered demonstrates that the Research Commons, designed primarily as a site for the creation of new knowledge in the form of original writing by researchers at postgraduate and academic level, is indeed an advance on the well‐established "library commons" concept, and that its creation represents an instance of "parallel invention" – the "new creature" that the title refers to. Originality/value – This paper provides a multifaceted perspective on the activities taking place in a new library facility and should provide librarians and researchers with evidence‐based insight into how meaningful research support may be provided to young researchers from diverse linguistic and cultural backgrounds as part of an academic library service in a middle income country.

(2003). EPA's Exposure Assessment Tools and Models. Applied Occupational and Environmental Hygiene: Vol. 18, No. 2, pp. 82-86.

A computer-derived treadmill exercise score that quantifies the electrocardiographic response to exercise has been reported to have a high sensitivity (87 per cent) and specificity (92 per cent) in patients with a high prevalence of coronary artery disease. To test its accuracy in young, asymptomatic men with a low prevalence of coronary artery disease, we evaluated the responses of 377 military officers (mean age, 36.6 years) by two independent methods. According to standard electrocardiographic criteria, 45 of the subjects (12 per cent) had positive tests, whereas the treadmill exercise score indicated that only 3 (less than 1 per cent) had positive tests. Since two of these three had left ventricular hypertrophy and met only the criteria for the latter without associated coronary artery disease, the treadmill exercise score predicted that only 1 of 377 subjects would have clinically important coronary artery disease. Coronary arteriography, performed in 10 persons with the most positive scores on standard treadmill tests and the highest scores for risk factors, showed that nine subjects did not have coronary artery disease and that one had single-vessel disease (the same subject who the treadmill score predicted would have mild disease). The treadmill exercise score appears to improve the diagnostic specificity of exercise electrocardiography and may be more useful than values on standard stress tests in screening asymptomatic populations for coronary artery disease.

The scope of this recital was great in many ways. It included the Prelude and Fugue from the Sonata in g minor for unaccompanied violin by Johann Sebastian Bach, the Sonata for Violin and Piano by Aaron Copland, Concerto no. III in b minor by Camille Saint-Saens, "On Wings of Song" by Felix Mendelssohn, and "Perpe tual Motion" by Ottakar Novacek. Performed were works of composers from three musical periods and representing three of the western worlds great musical countries -- the United States, Germany, and France. Stylistic demands ranged from the polyphonic form of the Bach Fugue, the lyrical singing style of the Saint-Saens violin Concerto, to the percussive qualities of the final movement in the Copland Sonata. Almost all violinistic technics were involved including scales; arpeggios; great leaps; double stops; harmonics; dynamic contrasts and nuances in tone color and vibrato; bowings such as spiccato, sautille, staccato, martele, and detache; as well as difficult pizzicato passages. The preparation of the performer has taken some twenty years and seven violin instructors at Utah State University. With this in mind and considering the importance of the several parts of the recital, this paper has been organized into the following sections: 1. The Violin, 2. The Composers, 3. The Music, its historical implications and form, 4. The Recital, and, 5. Epilogue. The Masters Recital is one of two options for partial fulfillment of a Master of Music or as in this case a Master of Arts degree in Music Education at Utah State University. The individual requirements for the recital are set up by the graduate committee which in this case consisted of Professor Ralph Matesky, chairman of the graduate committee, Dr . Max F. Dalby, committee member, and Dr. Keith Checketts, committee member.